Formation of L-Xylosone from Ascorbic Acid

DURING a study of the carbonyl compounds produced during cider fermentations an immediate precipitate ( A ) was obtained at room temperature on addition of dinitrophenylhydrazine to a sulphited cider (that is, a cider obtained from a juice to which 150 parts per million sulphur dioxide had been added after milling and pressing the fruit). A similar precipitate was formed in a sulphited Bramley Seedling juice which had failed to ferment, but no appreciable precipitate was noted in non-sulphited fermentations. The derivative ( A ) on a paper chromatogram gave a blue colour with sodium hydroxide solution which indicated the possibility of osazone formation. Owing to the difficulty of purifying the 2: 4-dinitrophenylhydrazine derivative, the phenylhydrazine derivative ( B ) was prepared from a sulphited cider at room temperature.